Deposition mask, method for manufacturing display unit using it, and display unit

ABSTRACT

A deposition mask and a display unit and method of manufacturing same are provided. A red continuous organic layer, a green continuous organic layer, and a blue continuous organic layer are provided over two or more lines of a matrix configuration of organic light emitting devices in common. A film thickness distribution in the extensional direction of the red, green and blue continuous organic layer is dissolved, and an aperture ratio can be improved by just that much.

CROSS REFERENCES TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No.P2003-132791, filed on May 12, 2003, the disclosure of which is hereinincorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a deposition mask, a method formanufacturing a display unit using same, and a display unit. Morespecifically the present invention relates to a deposition mask suitablefor manufacturing a display unit using organic light emitting devices, amethod for manufacturing a display unit using same, and a display unit.

In recent years, as a display unit instead of a liquid crystal display,an organic light emitting display which uses organic light emittingdevices has been used. The organic light emitting display hascharacteristics that its viewing angle is wide and its power consumptionis low since it is a self-luminous type display. The organic lightemitting display is also thought of as a display having sufficientresponse to high-definition high-speed video signals, and is underdevelopment toward the practical use.

A conventional organic light emitting display is manufactured throughprocesses of FIGS. 1 to 7. First, as shown in FIG. 1, a number of firstelectrodes 114 are formed on a substrate 111. These first electrodes 114are patterned for respective organic light emitting devices, andelectrically connected to unshown TFTs (Thin Film Transistor) which areprovided corresponding to respective organic light emitting devices withan unshown planarizing layer in between.

Next, as shown in FIG. 2, an insulating film 115 is formed in an areabetween the number of first electrodes 114. This insulating film 115 isprovided with openings 115A corresponding to the first electrodes 114.

Subsequently, as shown in FIG. 3, an auxiliary electrode 116A is formedat the position corresponding to the inside of picture on the insulatingfilm 115, and a trunk-shaped auxiliary electrode 116B which becomes abus line for the auxiliary electrode 116A is formed in a peripheral areaof the substrate 111. The auxiliary electrode 116A is provided in orderto uniform a wiring resistance between a power source (not shown) andrespective light emitting parts, and inhibit generation of emissionunevenness due to difference of voltage drop (particularly emissionunevenness between a central part and a peripheral part inside thepicture). Further, on an end of the trunk-shaped auxiliary electrode116B, an extraction electrode 116C is provided in order to connect asecond electrode 116 to the power source.

After that, for example, an organic layer 117 of an organic lightemitting device 110G generating green light is formed as shown in FIG.5, by using a deposition mask 140 having openings 141 corresponding torespective organic light emitting devices as shown in FIG. 4.

Next, as shown in FIG. 6, an organic layer 117 of an organic lightemitting device 110R generating red light is formed by moving thedeposition mask 140, and as shown in FIG. 5, an organic layer 117 of anorganic light emitting device 110B generating blue light is similarlyformed by moving the deposition mask 140 again.

Subsequently, as shown in FIG. 7, the second electrode 116 is formedalmost over the whole area of the substrate 111 by deposition method.The second electrode 116 and the auxiliary electrode 116A are therebyelectrically connected at a contact part 118.

Conventionally, for example, a case wherein a rib which serves as aspacer for a deposition mask to form an organic layer is providedbetween respective organic light emitting devices, and an auxiliaryelectrode is formed on this rib has been proposed. See, for example,Japanese Unexamined Patent Application Publication No. 2001-195008.

In the conventional deposition mask 140, the openings 141 are providedcorresponding to respective organic light emitting devices (FIG. 4).When deposition is performed by using such a deposition mask 140, a filmthickness distribution may be generated in the organic layer 117depending on conditions of deposition from an evaporation source 152, asshown in FIG. 8. Such a film thickness distribution varies depending ona plate thickness or a cross sectional shape of the deposition mask 140,or a physical relation between the evaporation source 152 and theopenings 141 of the deposition mask 140. In particular, the filmthickness distribution is subject to influence by characteristics of theevaporation source 152. Light emitting colors, that is, light emittingwavelengths of the organic light emitting devices depend on a filmthickness of the organic layer 117. Therefore, in order to prevent colorunevenness inside pixels, it is necessary to utilize only the area inthe vicinity of the center of the organic layer 117 having an even filmthickness as an effective light emitting region 117A. Therefore, therehas been a problem that when using the conventional deposition mask 140,the effective light emitting region 117A is limited, so that an apertureratio is lowered.

SUMMARY OF THE INVENTION

The present invention relates to a deposition mask, a method formanufacturing a display unit using same, and a display unit. Morespecifically the present invention relates to a deposition mask suitablefor manufacturing a display unit using organic light emitting devices, amethod for manufacturing a display unit using same, and a display unit.

In an embodiment, the present invention provides a deposition mask whichcan improve an aperture ratio of a display unit, and a method formanufacturing a display unit using the deposition mask.

In another embodiment, the present invention provides a display unitwhich is manufactured by using the deposition mask of the invention, andwhose aperture ratio is improved.

The deposition mask according to an embodiment of the present inventionis provided in order to form a continuous organic layer common toorganic light emitting devices of a display unit which has a matrixconfiguration constructed by a number of lines and columns of the numberof organic light emitting devices on a substrate by deposition method.The deposition mask according to an embodiment of the present inventionincludes a body part having one or more stripe-shaped openings to form acontinuous organic layer common to at least two lines of the matrixconfiguration, and protrusions which are provided on the body part topartly protrude inside the opening.

The method for manufacturing a display unit according to an embodimentof the present invention is a method to manufacture a display unithaving a matrix configuration constructed by a number of lines andcolumns of a number of organic light emitting devices on a substrate.The method for manufacturing a display unit according an embodiment ofto the present invention includes forming a number of first electrodesin the shape of a matrix corresponding to the respective number oforganic light emitting devices on the substrate; forming an insulatingfilm in an area between lines and columns of the number of firstelectrodes; forming an auxiliary electrode in an area between lines orcolumns of the number of first electrodes on the insulating film;forming a continuous organic layer common to at least two of the numberof first electrodes in the shape of a stripe by deposition, and notchparts at a position corresponding to an area between lines of the firstelectrodes of the stripe-shaped continuous organic layer; and forming asecond electrode covering almost a whole area of the substrate after thecontinuous organic layer having the notch parts is formed, a contactpart is formed at the notch parts of the continuous organic layer, andelectrically connecting the second electrode and the auxiliaryelectrode.

The display unit according to an embodiment of the present invention hasa matrix configuration constructed by a number of lines and columns of anumber of organic light emitting devices on a substrate. The displayunit according to the invention comprises: a number of first electrodesprovided on the substrate corresponding to the respective number oforganic light emitting devices; an insulating film provided in an areabetween lines or columns of the number of first electrodes; an auxiliaryelectrode provided in an area between lines or columns of the number offirst electrodes on the surface of the insulating film; a stripe-shapedcontinuous organic layer, which is provided over at least two lines of amatrix configuration of the number of organic light emitting devices incommon on the surface of the substrate including the number of firstelectrodes, and which has notch parts on its side wall partcorresponding to an area between lines of the number of firstelectrodes; and a second electrode, which covers almost a whole area ofthe substrate including the continuous organic layer, and which iselectrically connected to the auxiliary electrode through a contact partformed at the notch parts of the continuous organic layer.

In the deposition mask according to an embodiment of the presentinvention, the continuous organic layer common to at least two lines ofthe matrix configuration constructed by the number of lines and columnsof the number of organic light emitting devices is formed through thestripe-shaped opening provided on the body part of the deposition mask.Therefore, a film thickness distribution is decreased in the extensionaldirection of the continuous organic layer. Further, since theprotrusions are provided to partly protrude inside the opening, thenotch parts which become the contact part between the auxiliaryelectrode and the second electrode are formed on the continuous organiclayer.

In the method for manufacturing the display unit according to anembodiment of the present invention, the number of first electrodes areformed on the substrate in the shape of a matrix corresponding to therespective number of organic light emitting devices. Next, after theinsulating film is formed in the area between lines and columns of thenumber of first electrodes, the auxiliary electrode is formed on theinsulating film. Subsequently, the continuous organic layer common to atleast two of the number of first electrodes is formed in the shape of astripe by deposition, and the notch parts are formed at the positioncorresponding to the area between lines of the first electrodes of thestripe-shaped continuous organic layer. After that, the second electrodecovering almost the whole area of the substrate is formed, the contactpart is formed at the notch parts of the continuous organic layer, andthe second electrode and the auxiliary electrode are electricallyconnected.

In the display unit according to an embodiment of the present invention,the stripe-shaped continuous organic layer is provided over at least twolines of the matrix configuration of the number of organic lightemitting elements in common. Therefore, a film thickness distribution isdecreased in the extensional direction of the continuous organic layer.Further, the notch parts are provided on the side wall part of thecontinuous organic layer corresponding to the area between lines of thenumber of first electrodes, and the auxiliary electrode and the secondelectrode are electrically connected through the contact part formed atthese notch parts. Therefore, a wiring resistance difference between thepower source and respective organic light emitting devices is reduced.

In an embodiment, the present invention provides a deposition mask whichcan improve an aperture ratio of a display unit, a method formanufacturing a display unit using it, and a display unit. A redcontinuous organic layer, a green continuous organic layer, and a bluecontinuous organic layer are provided over two or more lines of a matrixconfiguration of organic light emitting devices in common. Differentlyfrom the conventional case wherein the organic layer is formedcorresponding to each organic light emitting device, a film thicknessdistribution in the extensional direction of the red continuous organiclayer, the green continuous organic layer, and the blue continuousorganic layer is dissolved, and an aperture ratio can be improved byjust that much. Notch parts are provided for the red continuous organiclayer, the green continuous organic layer, and the blue continuousorganic layer. At these notch parts, a contact part between a secondelectrode and an auxiliary electrode is formed. Therefore, voltage dropof the second electrode can be effectively inhibited.

Additional features and advantages of the present invention aredescribed in, and will be apparent from, the following DetailedDescription of the Invention and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a plane view to explain a method for manufacturing aconventional display unit.

FIG. 2 is a plane view to explain a manufacturing process following aprocess of FIG. 1.

FIG. 3 is a plane view to explain a manufacturing process following theprocess of FIG. 2.

FIG. 4 is a plane view to explain a manufacturing process following theprocess of FIG. 3.

FIG. 5 is a plane view to explain a manufacturing process following theprocess of FIG. 4.

FIG. 6 is a plane view to explain a manufacturing process following theprocess of FIG. 5.

FIG. 7 is a plane view to explain a manufacturing process following theprocess of FIG. 6.

FIG. 8 is a cross sectional view to explain a problem area of adeposition mask used in manufacturing the conventional display unit.

FIG. 9 is a plane view showing an outline construction of a display unitaccording to an embodiment of the present invention.

FIG. 10 is a cross sectional view to explain a manufacturing process ofthe display unit shown in FIG. 9.

FIG. 11 is a plane view regarding a manufacturing process following theprocess of FIG. 10.

FIG. 12 is a cross sectional view taken along line IV-IV of FIG. 11.

FIG. 13 is a plane view regarding a manufacturing process following theprocesses of FIGS. 11 and 12.

FIG. 14 is a cross sectional view taken along line VI-VI of FIG. 13.

FIG. 15 is a plane view regarding a manufacturing process following theprocesses of FIGS. 13 and 14.

FIG. 16 is a cross sectional view taken along line VIII-VIII of FIG. 15.

FIG. 17 is a cross sectional view regarding a manufacturing processfollowing the processes of FIGS. 15 and 16.

FIG. 18 is a plane view showing a construction of a deposition maskshown in FIG. 17.

FIG. 19 is a plane view showing a condition wherein a green continuousorganic layer is formed by using the deposition mask shown in FIGS. 17and 18.

FIG. 20 is a plane view showing a modification of the deposition maskshown in FIG. 18.

FIG. 21 is a plane view showing other modification of the depositionmask shown in FIG. 18.

FIG. 22 is a view regarding an outline construction of a depositionapparatus used in the processes of FIGS. 17 and 19.

FIG. 23 is a plane view regarding a manufacturing process following theprocesses of FIGS. 17 and 19.

FIG. 24 is a plane view regarding a manufacturing process following theprocess of FIG. 23.

FIG. 25 is a cross sectional view taken along line XVII-XVII of FIG. 24.

FIG. 26 is a cross sectional view taken along line XVIII-XVIII of FIG.24.

FIG. 27 is a plane view regarding a manufacturing process following theprocess of FIG. 24.

FIG. 28 is a cross sectional view taken along line XX-XX of FIG. 27.

FIG. 29 is a cross sectional view taken along line XXI-XXI of FIG. 27.

FIG. 30 is a cross sectional view to regarding a manufacturing processfollowing the process of FIG. 27.

FIGS. 31A and 31B are cross sectional views regarding manufacturingprocesses following the process of FIG. 30.

FIG. 32 is a cross sectional view regarding a manufacturing processfollowing the processes of FIGS. 31A and 31B.

FIG. 33 is a cross sectional view regarding a manufacturing processfollowing the process of FIG. 32.

FIG. 34 is a view regarding an operation of a display unit shown in FIG.33.

FIG. 35 is a plane view showing still another modification of thedeposition mask shown in FIG. 18.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a deposition mask, a method formanufacturing a display unit using same, and a display unit. Morespecifically the present invention relates to a deposition mask suitablefor manufacturing a display unit using organic light emitting devices, amethod for manufacturing a display unit using same, and a display unit.

An embodiment of the present invention will be described in detailhereinbelow with reference to the drawings.

With reference to FIGS. 9 to 31B, a method for manufacturing a displayunit according to an embodiment of the invention and a deposition maskused for the display unit will be described. This display unit is used,for example, as an ultra thin organic light emitting display. As shownin FIG. 9, many pixels are arranged in the shape of a matrix as a wholeby constructing a matrix configuration constructed by a number of linesand columns of organic light emitting devices 10R, 10G, and 10B on asubstrate 11, setting three primary colors device of the organic lightemitting device 10R generating red light, the organic light emittingdevice 10G generating green light, and the organic light emitting device10B generating blue light to one pixel unit.

In this embodiment, before such organic light emitting devices 10R, 10G,and 10B are formed, first, as shown in FIG. 10, a TFT 12 is formed onthe substrate 11 made of an insulating material such as glass, then aninterlayer insulating film 12A made of, for example, silicon oxide, PSG(Phospho-Silicate Glass) or the like is formed. After that, a wiring 12Bmade of, for example, aluminum (Al) or an aluminum (Al)-copper (Cu)alloy is formed as a signal line. A gate electrode (not shown) of theTFF 12 is connected to an unshown scanning circuit. A source and a drain(not shown either) are connected to the wiring 12B through an unshowncontact hole provided on the interlayer insulating film 12A. Aconstruction of the TFT 12 is not limited particularly, and can beeither a bottom gate type or a top gate type, for example.

Next, as shown in FIG. 10 as well, a planarizing layer 13 made of anorganic material such as polyimide is formed on the whole area of thesubstrate 11 by, for example, spin coat method. The planarizing layer 13is patterned in a given shape by exposure and development, and a contacthole 13A is formed. The planarizing layer 13 is provided in order toplanarize the surface of the substrate 11 wherein the TFT 12 is formed,and evenly form a film thickness in the direction of layers (hereinafterreferred to as “thickness”) of respective layers of the organic lightemitting devices 10R, 10G, and 10B formed in a subsequent process. Theplanarizing layer 13 is preferably made of a material having a desirablepattern precision, since the fine contact hole 13A is formed. As amaterial for the planarizing layer 13, an inorganic material such assilicon oxide (SiO₂) or the like can be used, instead of the organicmaterial such as polyimide or the like.

Subsequently, as shown in FIGS. 11 and 12, first electrodes (individualelectrodes) 14 are formed in the shape of a matrix on the planarizinglayer 13 corresponding to respective devices by, for example, spatteringand lithography technique. The first electrodes 14 are connected to thewiring 12B through the contact hole 13A. The first electrode 14 also hasa function as a reflection layer. For example, the first electrode 14preferably has a thickness of about 200 nm, and is made of a substanceor an alloy of a metal element having a high work function, such asplatinum (Pt), gold (Au), silver (Ag), chromium (Cr), tungsten (W) orthe like.

After that, as shown in FIGS. 13 and 14, an insulating film 15 is formedin an area between lines and columns of the first electrodes 14 by, forexample, CVD (Chemical Vapor Deposition) method and lithographytechnique, and openings 15A are formed corresponding to light emittingregion. The insulating film 15 is provided in order to secure insulationbetween the first electrodes 14 and a second electrode 16, which will bedescribed later, and accurately obtain a desired shape of light emittingregion in the organic light emitting devices 10R, 10G, and 10B. Forexample, the insulating film 15 has a thickness of about 600 nm, and ismade of an insulating material such as silicon oxide, polyimide and thelike.

Next, as shown in FIGS. 15 and 16, an auxiliary electrode 16A is formedin the shape of a matrix on the insulating film 15 by, for example,spattering and lithography technique. The auxiliary electrode 16A isprovided in order to uniform a wiring resistance between a power source(not shown) and respective light emitting parts, and inhibit generationof emission unevenness (particularly emission unevenness between acentral part and a peripheral part inside a picture) due to a differenceof voltage drop. For example, the auxiliary electrode 16A has amonolayer structure or a layered structure of a conductive materialhaving a low resistance, such as aluminum (Al), chromium (Cr) and thelike. Further, as shown in FIGS. 15 and 16 as well, a trunk-shapedauxiliary electrode 16B which becomes a bus line of the auxiliaryelectrode 16A is formed in a peripheral area of the substrate 11 by, forexample, spattering and lithography technique. The trunk-shapedauxiliary electrode 16B is made of a material similar to for theauxiliary electrode 16A, for example. However, since the trunk-shapedauxiliary electrode 16B is formed in the peripheral area of thesubstrate 11, its thickness and width can be made larger than that ofthe auxiliary electrode 16A. That is, it is possible to further lower awiring resistance. The trunk-shaped auxiliary electrode 16B and theauxiliary electrode 16A are electrically connected by, for example,forming them so that ends of the auxiliary electrode 16A contact withthe trunk-shaped auxiliary electrode 16B. The trunk-shaped auxiliaryelectrode 16B can be either formed integrally with the auxiliaryelectrode 16A in the same process, or formed in other process. Inaddition, the trunk-shaped auxiliary electrode 16B can be formed on thesubstrate 11. In this case, electrical connection between thetrunk-shaped auxiliary electrode 16B and the auxiliary electrode 16A canbe conducted with the planarizing layer 13 in between through thecontact hole.

An extraction electrode 16C is provided at an end of the trunk-shapedauxiliary electrode 16B in order to connect the second electrode 16 tothe power source (not shown). This extraction electrode 16C can be madeof, for example, titanium (Ti)-aluminum (Al) or the like.

Subsequently, as shown in FIGS. 17 and 18, a green continuous organiclayer 17G common to the organic light emitting devices 10G is formed bydeposition method by using a deposition mask 40 having stripe-shapedopenings 41. As shown in FIG. 19, the green continuous organic layer 17Ghaving, for example, semioval notches 17A in an area between the organiclight emitting devices 10G is thereby formed.

As the green continuous organic layer 17G, for example, an electron holetransport layer and a light emitting layer are layered in this orderfrom the first electrode 14 side. The electron hole transport layer isprovided in order to raise electron hole injection efficiency to thelight emitting layer. The light emitting layer is provided in order toreconnect electrons and electron holes and generate light by applyingelectric field. Examples of the component material for the electron holetransport layer of the green continuous organic layer 17G include α-NPDand the like. Examples of the component material for the light emittinglayer of the green continuous organic layer 17G include one whereinCoumarin 6 (C6) of 1 vol % is mixed with 8-quinolinol aluminum complex(Alq₃).

The deposition mask 40 shown in FIGS. 17 and 18 includes a flatplate-shaped body part 40A made of a material having magneticcharacteristics such as nickel (Ni) and an alloy containing nickel, andone or more, such as two, stripe-shaped openings 41. The opening 41 isarranged and formed so that a number of devices of the organic lightemitting devices 10R, 10G, or 10B whose light emitting color is the samecan be simultaneously formed. For example, as shown in FIGS. 17 and 18,the green continuous organic layer 17G common to the organic lightemitting devices 10G can be formed by performing deposition by aligningthe opening 41 with a position where the organic light emitting devices10G can be formed. In this embodiment, the green continuous organiclayer 17G is formed for a number, such as three, of organic lightemitting devices 10G in common, differently from the conventional case,wherein the organic layer is formed for each organic light emittingdevice 10G. Therefore, generation of a film thickness distribution inthe extensional direction of the green continuous organic layer 17G isdissolved. Consequently, its light emitting region can be expanded byjust that much, and its aperture ratio can be raised.

In this embodiment, the body part 40A includes protrusions 41A toprotrude inside the opening 41. The protrusion 41A is provided in orderto provide the notch part 17A, which will be described later, on thegreen continuous organic layer 17G corresponding to an area betweenlines of the adjacent organic light emitting devices 10G. Theprotrusions 41A are, for example, provided as a pair at the relativepositions on both sides in the width direction of the opening 41. Thereare a number of pairs (i.e., two pairs) of the protrusions 41A so thatthese pairs can correspond to respective positions between lines of theorganic light emitting devices 10G.

A shape of the protrusion 41A is preferably set not to block the opening15A of the insulating film 15, that is a light emitting region. If setas above, an after-mentioned contact part 18 between the auxiliaryelectrode 16A and the second electrode 16 can be provided withoutpreventing improvement of an aperture ratio. Concrete examples of theshape of the protrusion 41A include the semioval shape shown in FIG. 18,a round shape such as semicircle (not shown), a triangle as shown inFIG. 20, and a non-circular shape such as a rectangle as shown in FIG.21. Dimensions of the protrusion 41A are set as appropriate byconsidering a plate thickness of the deposition mask 40, positionrelation with the light emitting region, dimensions of the contact part18 and the like. In this embodiment, dimensions of the protrusion 41Aare set, for example, as follows: a dimension in the extensionaldirection of the opening 41, d1 is about 40 nm, and a dimension (width)in the direction perpendicular to the extensional direction of theopening 41, d2 is about 30 nm. The opening 41 and the protrusion 41A canbe formed, for example, by etching or electroforming method.

FIG. 22 shows an outline construction of a deposition apparatus to formthe green continuous organic layer 17G by using such a deposition mask40. This deposition apparatus 50 includes a deposition source 52 housingan organic material, which is a component material for the greencontinuous organic layer 17G inside a vacuum chamber 51. A work 53wherein the deposition mask 40 is attached to the substrate 11 isarranged facing to the deposition source 52. Though unshown, a carry-inentrance and a vent for the work 53 are provided for the vacuum chamber51.

A construction of the deposition source 52 is not particularly limited,and can be either a point source or a line source. As the depositionsource 52, a resistance deposition source, an EB (Electron Beam)deposition source or the like can be used. The deposition source 52 canbe provided respectively for the electron hole transport layer and thelight emitting layer, the components for the green continuous organiclayer 17G.

The work 53 can be either rotatable at a fixed position over thedeposition source 52, or relatively movable in relation to thedeposition source 52. The deposition mask 40 is attached on thesubstrate 11 on the deposition source 52 side, being held by a maskholder 54, and fixed by a sheet magnet 55 provided on the rear side ofthe substrate 11.

After the green continuous organic layer 17G is formed as above, thedeposition mask 40 is aligned with a position where the organic lightemitting devices 10R are to be formed, and a red continuous organiclayer 17R, which has the notch parts 17A and which is common to theorganic light emitting devices 10R is formed as shown in FIG. 23. Aforming method for the red continuous organic layer 17R and a depositionapparatus used for it are similar to in the case of the green continuousorganic layer 17G of the organic light emitting device 10G.Consequently, the notch part 17A of the green continuous organic layer17G and the notch part 17A of the red continuous organic layer 17R arealigned, and in the aligned area, the auxiliary electrode 16A isexposed.

As the red continuous organic layer 17R, for example, an electron holetransport layer, a light emitting layer, and an electron transport layerare layered in this order from the first electrode 14 side. The electrontransport layer is provided in order to raise electron injectionefficiency to the light emitting layer. As a component material for theelectron hole transport layer of the red continuous organic layer 17R,for example, bis[(N-naphthyl)-N-phenyl] benzidine (a-NPD) can beemployed. As a component material for the light emitting layer of thered continuous organic layer 17R, for example, 2,5-bis[4-[N-(4-methoxyphenyl)-N-phenyl amino]] styryl benzene-1,4-dicarbonitrile (BSB) can beemployed. As a component material for the electron transport layer ofthe red continuous organic layer 17R, for example, Alq₃ can be employed.

Subsequently, the deposition mask 40 is moved again, and a bluecontinuous organic layer 17B which has the notch parts 17A and which iscommon to the organic light emitting devices 10B is formed as shown inFIGS. 24, 25, and 26. A method for forming the blue continuous organiclayer 17B and a deposition apparatus used for it are similar to in thecase of the green continuous organic layer 17G of the organic lightemitting device 10G. Consequently, the notch part 17A of the bluecontinuous organic layer 17B and the notch part 17A of the greencontinuous organic layer 17G are aligned, and in the aligned area, theauxiliary electrode 16A is exposed. Further, the notch part 17A of theblue continuous organic layer 17B and the notch part 17A of the redcontinuous organic layer 17R are aligned, and in the aligned area, theauxiliary electrode 16A is exposed.

As the blue continuous organic layer 17B, for example, an electron holetransport layer, a light emitting layer, and an electron transport layerare layered in this order from the first electrode 14 side. As acomponent material for the electron hole transport layer of the bluecontinuous organic layer 17B, for example, α-NPD can be employed. As acomponent material for the light emitting layer of the blue continuousorganic layer 17B, for example, 4,4′-bis (2,2′-diphenyl vinyl) biphenyl(DPVBi) can be employed. As a component material for the electrontransport layer of the blue continuous organic layer 17B, for example,Alq₃ can be employed.

After the red continuous organic layer 17R, the green continuous organiclayer 17G, and the blue continuous organic layer 17B are formed, asshown in FIGS. 27, 28, and 29, the second electrode 16 covering almost awhole area of the substrate 11 is formed by, for example, depositionmethod. The second electrode 16 includes a semi-transparent electrode,and light generated in the light emitting layer is extracted from thesecond electrode 16 side. For example, the second electrode 16 has athickness of about 10 nm, and made of metal such as silver (Ag),aluminum (Al), magnesium (Mg), calcium (Ca), and sodium (Na), the likeor an alloy thereof. In this embodiment, for example, the secondelectrode 16 includes an alloy (MgAg alloy) of magnesium (Mg) andsilver.

By forming the second electrode 16 to cover almost the whole area of thesubstrate 11, the contact part 18 between the auxiliary electrode 16Aand the second electrode 16 is formed at the notch part 17A, and theauxiliary electrode 16A and the second electrode 16 are electricallyconnected. Further, the second electrode 16 is formed to cover at leastpart of the trunk-shaped auxiliary electrode 16B, so that the secondelectrode 16 and the trunk-shaped auxiliary electrode 16B areelectrically connected. The organic light emitting devices 10R, 10G, and10B are thereby formed.

Next, as shown in FIG. 30, a protective film 19 is formed on the secondelectrode 16 by, for example, deposition method, CVD method, spatteringor the like. For example, the protective film 19 has a thickness fromabout 500 nm to about 10,000 nm, and includes a transparent dielectricsuch as silicon oxide (SiO₂), silicon nitride (SiN) and the like.

As shown in FIG. 31A, for example, on a sealing substrate 21 made of amaterial such as glass transparent to light generated in the organiclight emitting devices 10R, 10G, and 10B, a red filter 22R is formed byapplying a material for the red filter 22R by spin coat or the like bypatterning with photolithography technique and by firing. Subsequently,as shown in FIG. 31B, a blue filter 22B and a green filter 22G aresequentially formed in a manner similar to in the red filter 22R. A.color filter 22 is thereby formed on the sealing substrate 21. The colorfilter 22 is provided in order to extract light generated in the organiclight emitting devices 10R, 10G, and 10B, absorb outside light reflectedin the organic light emitting devices 10R, 10G, and 10B, and the wiringtherebetween, and improve the contrast.

After that, as shown in FIG. 32, an adhesive layer 30 made of, forexample, a thermosetting resin is formed by coating on the side wherethe organic light emitting devices 10R, 10G, and 10B are formed of thesubstrate 11. Coating can be made by, for example, discharging a resinfrom a slit nozzle type dispenser, roll coating, or screen printing.Next, as shown in FIG. 33, the substrate 11 and the sealing substrate 21are bonded together with the adhesive layer 30 in between. In thisregard, it is preferable that a side of the sealing substrate 21 wherethe color filter 22 is formed is arranged facing to the substrate 11. Itis preferable that air bubbles or the like does not enter into theadhesive layer 30. After that, relative positions of the color filter 22of the sealing substrate 21 and the organic light emitting devices 10R,10G, and 10B of the substrate 11 are aligned. Then, the thermosettingresin of the adhesive layer 30 is cured by heat treatment for a giventime at a given temperature. The display unit according to thisembodiment is thereby completed.

In the display unit manufactured as above, when a given voltage isapplied between the first electrodes 14 and the second electrode 16,current is injected in the light emitting layer of the continuousorganic layer 17, electron holes and electrons are recombined.Consequently, light emitting is generated. This light is extracted fromthe sealing substrate 21 side. In this case, the red continuous organiclayer 17R is provided for the number of (three in FIG. 19) organic lightemitting devices 10R in common, the green continuous organic layer 17 Gis provided for the number of organic light emitting devices 10G incommon, and the blue continuous organic layer 17B is provided for thenumber of organic light emitting devices 10B in common, respectively.Therefore, differently from the conventional case of forming the organiclayers corresponding to respective organic light emitting devices, eachdevice is free from or without a film thickness distribution in theextensional direction of the red continuous organic layer 17R and so on,and has an even thickness.

Further, the notch parts 17A are provided at a position corresponding toa non-light emitting region (that is, an area between lines of thematrix configuration) of the red continuous organic layer 17R, the greencontinuous organic layer 17G, and the blue continuous organic layer 17B.Therefore, the contact part 18 between the second electrode 16 and theauxiliary electrode 16A is formed for each device without lowering theaperture ratio.

FIG. 34 shows an equivalent circuit diagram of a connection circuit partbetween respective devices and the extraction electrode 16C. Since thesecond electrode 16 includes a thin film common electrode, a resistancecomponent R1 between the extraction electrode 16C and the device closestto the extraction electrode 16C, and resistance components R2 and R3between devices are high, and voltage drop varies depending ondifferences of distance between respective devices and the extractionelectrode 16C, causing luminance variation between the central part andthe peripheral part in the display screen. In this embodiment, thesecond electrode 16 is electrically connected to the auxiliary electrode16A through the contact part 18 at the position corresponding torespective devices. The auxiliary electrode 16A has a thick filmthickness, and a resistance component R4 between the extractionelectrode 16C and the device closest to the extraction electrode 16C,and resistance components R5 and R6 between devices are relatively smallcompared to resistance components R1 to R3. That is, in a route from theextraction electrode 16C to respective devices through the auxiliaryelectrode 16A and the contact part 18, wiring resistance differencesbetween the extraction electrode 16C and respective devices are reducedand uniformed. Therefore, current sent from the power source (not shown)and supplied through the electrode 16C is applied to respective devicesthrough the auxiliary electrodes 16A and the contact part 18 withoutraising any large difference in voltage drop. Consequently, display isrealized with an even luminance over the whole screen.

As above, in this embodiment, the red continuous organic layer 17R, thegreen continuous organic layer 17G, and the blue continuous organiclayer 17B are provided for the number of organic light emitting devices10R, 10G, and 10B in common, respectively. Therefore, a film thicknessdistribution is dissolved in the extensional direction of the redcontinuous organic layer 17R, the green continuous organic layer 17G,and the blue continuous organic layer 17B, and an aperture ratio can beimproved by-just that much. Further, the contact part 18 between thesecond electrode 16 and the auxiliary electrode 16A is formed at thenotch parts 17A formed in the non-light emitting region of respectivecontinuous organic layers. Therefore, the contact part 18 can be formedcorresponding to respective devices inside the panel, and wiringresistance differences between the extraction electrode 18C andrespective devices can be reduced and uniformed. Consequently, luminancevariation between the center and the peripheral part in the displayscreen can be remedied.

While the invention has been described with reference to the embodiment,the invention is not limited to the foregoing embodiment, and variousmodifications may be made. For example, in the foregoing embodiment, thecase wherein the protrusions 41A are provided so that these protrusions41A make a pair at the relative positions on the both sides in the widthdirection of the opening 41, and the notch parts 17A are positionedadjacent to each other has been described. However, as shown in FIG. 35,it is possible that a long protrusion 41C is provided in the widthdirection only at one side in the width direction of the opening 41, andthe contact part 18 is formed without positioning the notch parts 17Aadjacent to each other. However, the foregoing embodiment is preferable,since it is possible to surely obtain the effect to improve an apertureratio by reducing a film thickness distribution in the extensionaldirection of the red continuous organic layer 17R, the green continuousorganic layer 17G, and the blue continuous organic layer 17B. When theprotrusion 41C is provided only at one side in the width direction ofthe opening 41, it is not always necessary to provide the protrusions 41only at the same side in the width direction of the opening 41.

In the foregoing embodiment, the case wherein the organic light emittingdevices 10R, 10G, and 10B are respectively arranged in line, and the redcontinuous organic layer 17R, the green continuous organic layer 17G,and the blue continuous organic layer 17B are formed in the shape of astraight stripe has been described. However, it is no problem as long asthe red continuous organic layer 17R, the green continuous organic layer17G, and the blue continuous organic layer 17B are formed for two ormore lines of the organic light emitting devices 10R, 10G, and 10B incommon. It is not necessarily that the organic light emitting devices10R, 10d, and 10B are respectively arranged in line. For example, it ispossible that the organic light emitting devices 10R, 10G, and 10B arearranged in the staggered shape.

In the foregoing embodiment, the case wherein the auxiliary electrode16A is formed in the shape of a matrix in the area between lines andcolumns of the first electrodes 14 on the insulating film 15 has beendescribed. However, the auxiliary electrode 16A can be provided only inthe area between lines of the first electrodes 14, or only in the areabetween columns of the first electrodes 14.

The materials, thicknesses, deposition methods, deposition conditionsand the like of respective layers are not limited to those described inthe foregoing embodiment. Other materials, thicknesses, depositionmethods, and deposition conditions can be applied. For example,film-forming order of the red continuous organic layer 17R, the greencontinuous organic layer 17G, and the blue continuous organic layer 17Bis not limited to the order described in the foregoing embodiment.

For example, in the foregoing embodiment, the case wherein the firstelectrodes 14, the continuous organic layer 17, and the second electrode16 are layered in this order from the substrate 11 side, and light isextracted from the sealing substrate 21 side has been described.However, light can be extracted from the substrate 11 side. However, inthe foregoing embodiment, the TFTs 12 are provided on the substrate 11corresponding to the respective organic light emitting devices 10R, 10Gand 10B, and the organic light emitting devices 10R, 10G and 10B aredriven by these TFTs 12. Therefore, it is more beneficial to extractlight from the sealing substrate 21 side wherein no TFTs 12 areprovided, since an aperture ratio becomes large and effect of theinvention can be further improved.

For example, in the foregoing embodiment, the case wherein the firstelectrode 14 is set to an anode and the second electrode 16 is set to acathode. However, it is possible that the anode and the cathode areinversed, that is, the first electrode 14 can be set to a cathode andthe second electrode 16 can be set to an anode. Further, along withsetting the first electrode 14 to the cathode and the second electrode16 to the anode, it is possible to extract light from the substrate 11side.

In the foregoing embodiment, the concrete example of the construction ofthe organic light emitting devices 10R, 10G, and 10B has been described.However, it is not necessary that all layers are provided. In addition,other layers can be further provided. Layer constructions and componentmaterials for the red continuous organic layer 17R, the green continuousorganic layer 17G, and the blue continuous organic layer 17B of theorganic light emitting devices 10R, 10G, and 10B are not limited to thecase in the foregoing embodiment.

In the foregoing embodiment, the case wherein the invention is appliedto the color display has been described. However, the invention can beapplied to the case of a mono-color display.

As described above, according to the deposition mask of the inventionand the method for manufacturing the display unit of the invention, thecontinuous organic layer common to at least two lines of the matrixconfiguration of the number of organic light emitting devices is formedthrough the stripe-shaped opening provided on the body part of thedeposition mask. Therefore, a film thickness distribution in theextensional direction of the continuous organic layer can be dissolved,and an aperture ratio can be improved by just that much. Further, in thedeposition mask, the protrusions are provided to partly protrude insidethe opening. Therefore, the notch parts to become the contact partbetween the auxiliary electrode and the second electrode (commonelectrode) can be formed on the continuous organic layer, and wiringresistance differences between the power source and respective devicescan be reduced and uniformed. Consequently, a luminance variationbetween the center and the peripheral part of the display screen can beimproved.

According to the display unit of the invention, the auxiliary electrodeand the second electrode are electrically connected through the contactpart formed at the notch parts of the continuous organic layer.Therefore, current supplied from the power source can be applied torespective devices through the auxiliary electrode and the contact partwithout generating large difference in voltage drop. Consequently, aluminance variation between the center and the peripheral part of thedisplay screen can be improved, and display can be realized with evenluminance over the whole area of the screen.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present invention andwithout diminishing its intended advantages. It is therefore intendedthat such changes and modifications be covered by the appended claims.

1. A deposition mask that forms a continuous organic layer common to aplurality of organic light emitting devices of a display unit that has amatrix configuration constructed by a plurality of lines and columnsassociated with the organic light emitting devices on a substrate bydeposition, comprising: a body part having one or more stripe-shapedopenings to form a continuous organic layer common to at least two linesof the matrix configuration; and one or more protrusions that areprovided on the body part wherein the protrusions partly protrude insidethe one or more stripe-shaped openings.
 2. The deposition mask accordingto claim 1, wherein the protrusions are provided corresponding to anarea between the lines of the organic light emitting devices.
 3. Thedeposition mask according to claim 1, wherein the protrusions are in ashape selected from the group consisting of a semicircle, a semiellipse,and a polygon.
 4. The deposition mask according to claim 1, wherein theprotrusions are provided as a pair at relative positions on both sidesin a width direction of the one or more stripe-shaped openings.
 5. Thedeposition mask according to claim 4, wherein a plurality of pairs ofthe protrusions are provided corresponding to respective positionsbetween the lines of the organic light emitting devices.
 6. Thedeposition mask according to claim 1, wherein the one or morestripe-shaped openings are formed by any one of etching andelectroforming.
 7. The deposition mask according to claim 1, wherein thebody part includes a material having magnetic characteristics.
 8. Amethod for manufacturing a display unit having a matrix configurationconstructed by a plurality of lines and columns of a plurality oforganic light emitting devices on a substrate, comprising: forming aplurality of first electrodes in a shape of a matrix corresponding tothe respective plurality of organic light emitting devices on thesubstrate; forming an insulating film in an area between the lines andcolumns of the plurality of first electrodes; forming an auxiliaryelectrode in an area between the lines and columns of the plurality offirst electrodes on the insulating film; forming a continuous organiclayer common to at least two of the plurality of first electrodes in ashape of a stripe by deposition, and notch parts at a positioncorresponding to an area between the lines of the first electrodes ofthe stripe-shaped continuous organic layer; and forming a secondelectrode covering a substantially whole area of the substrate after thecontinuous organic layer having the notch parts is formed, a contactpart is formed at the notch parts of the continuous organic layer, andelectrically connecting the second electrode and the auxiliaryelectrode.
 9. The method for manufacturing a display unit according toclaim 8, wherein the continuous organic layer having the notch parts isformed by using a deposition mask comprising a body part having one ormore stripe-shaped openings and protrusions provided on the body partthat partly protrude inside the opening.
 10. The method formanufacturing a display unit according to claim 8, wherein the notchparts are formed in a shape selected from the group consisting of asemicircle, a semiellipse, and a polygon.
 11. The method formanufacturing a display unit according to claim 8, wherein atrunk-shaped auxiliary electrode that becomes a bus line for theauxiliary electrode is formed in a peripheral area of the substrate. 12.A display unit having a matrix configuration constructed by a pluralityof lines and columns of a plurality of organic light emitting devices ona substrate, comprising: a plurality of first electrodes provided on thesubstrate corresponding to the respective plurality of organic lightemitting devices; an insulating film provided in an area between thelines and columns of the plurality of first electrodes; an auxiliaryelectrode provided in an area between the lines and columns of theplurality of first electrodes on the surface of the insulating film, astripe-shaped continuous organic layer, that is provided over at leasttwo lines of a matrix configuration of the plurality of organic lightemitting devices in common on the surface of the substrate including theplurality of first electrodes, and that has one or more notch parts on aside wall part corresponding to an area between lines of the pluralityof first electrodes; and a second electrode, that substantially covers awhole area of the substrate including the continuous organic layer, andwhich is electrically connected to the auxiliary electrode through acontact part formed at the notch parts of the continuous organic layer.13. The display unit according to claim 12, wherein the continuousorganic layer having the notch parts is formed by using a depositionmask comprising a body part having one or more stripe-shaped openingsand protrusions provided on the body part to partly protrude inside theopening.
 14. The display unit according to claim 12, wherein the notchparts are in a shape selected from the group consisting of a semicircle,a semiellipse, and a polygon.
 15. The display unit according to claim12, wherein a trunk-shaped auxiliary electrode that becomes a bus linefor the auxiliary electrode is formed in a peripheral area of thesubstrate.
 16. The display unit according to claim 12, wherein theorganic light emitting device extracts light generated in the continuousorganic layer from the second electrode side.
 17. The display unitaccording to claim 12, wherein a sealing substrate is arranged facing tothe substrate on a side of the plurality of organic light emittingdevice of the substrate, and the substrate and the sealing substrate arebonded together over a whole area thereof with an adhesive layer inbetween.